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Thread: Aerials: 125-150mm sharp@ f/8 for 4x5 minimal vignetting

  1. #41

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    Re: Aerials: 125-150mm sharp@ f/8 for 4x5 minimal vignetting

    In closing, thanks to all who shared useful information on commonly available lenses for 4x5 per my well-defined needs in the opening post.

    As a side note, the interesting thing about my father, a highly decorated USAF combat and test pilot, is that he never bragged. Never mentioned that he had a single commendation. But then, that was the Greatest Generation.

    PaulOUT
    Dallas Texas HABS / HAER / HALS Photography
    Photographer/Author Marfa Flights: Aerial Views of Big Bend Country (Texas A&M University Press)
    Represented by Michael Duty Fine Art

  2. #42

    Re: Aerials: 125-150mm sharp@ f/8 for 4x5 minimal vignetting

    Quote Originally Posted by Jim Michael View Post
    Vibration tends to be a factor as well.
    Yes - in small aircraft vibration and buffeting is by far the major factor. From a Cessna I've found it easy to pan to compensate for the general motion of the plane but only a high shutter speed, and/or a camera gyroscope will compensate for aircraft vibration and buffeting. (With smaller formats, image stabilization in-lens or in-body may be helpful in some circumstances.)
    Bill

  3. #43

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    Re: Aerials: 125-150mm sharp@ f/8 for 4x5 minimal vignetting

    Quote Originally Posted by pchaplo View Post
    I may start with a slightly longer lens ie Nikkor 200mm M f/8. I believe that wide open, the image circle is 166mm. If anyone has real life experience with that lens in terms of coverage - and corner sharpness (a long shot, I know) - at f/8 let me know.
    This is the lp/mm performance measured by Mr Perez of a M 200mm sample

    f/11 68 76 38 (Center Mid Edge)
    f/16 68 68 34
    f/22 60 54 48

    http://www.hevanet.com/cperez/testing.html

    Still not a lab test but a practical one, and we have to remember that from one unit to another one there is a variability.

  4. #44

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    Re: Aerials: 125-150mm sharp@ f/8 for 4x5 minimal vignetting

    I have Kenyon gyro if needed.

    Quote Originally Posted by Photomagica View Post
    Yes - in small aircraft vibration and buffeting is by far the major factor. From a Cessna I've found it easy to pan to compensate for the general motion of the plane but only a high shutter speed, and/or a camera gyroscope will compensate for aircraft vibration and buffeting. (With smaller formats, image stabilization in-lens or in-body may be helpful in some circumstances.)
    Bill
    Dallas Texas HABS / HAER / HALS Photography
    Photographer/Author Marfa Flights: Aerial Views of Big Bend Country (Texas A&M University Press)
    Represented by Michael Duty Fine Art

  5. #45

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    Re: Aerials: 125-150mm sharp@ f/8 for 4x5 minimal vignetting

    Great site. I’m really enjoying his writings, images, and lens tests/comparisons. Thanks.

    Quote Originally Posted by Pere Casals View Post
    This is the lp/mm performance measured by Mr Perez of a M 200mm sample

    f/11 68 76 38 (Center Mid Edge)
    f/16 68 68 34
    f/22 60 54 48

    http://www.hevanet.com/cperez/testing.html

    Still not a lab test but a practical one, and we have to remember that from one unit to another one there is a variability.
    Dallas Texas HABS / HAER / HALS Photography
    Photographer/Author Marfa Flights: Aerial Views of Big Bend Country (Texas A&M University Press)
    Represented by Michael Duty Fine Art

  6. #46

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    Re: Aerials: 125-150mm sharp@ f/8 for 4x5 minimal vignetting

    Quote Originally Posted by Oren Grad View Post

    EDIT: My Nikkor lens literature has wide-open specs too. But in the Nikkor SW line, the 90mm f/8 won't do and probably not the 90/4.5 either - you really need to go to the 120 to get adequate coverage at f/8 on 4x5, and that's a fairly large and heavy lens. In the Nikkor W line, the 135 has tight coverage relative to 4x5 at f/5.6 (156mm), while the 150 covers 174mm.
    Im re-reading all your most helpful notes. Very helpful info and greatly appreciated. The f/5.6 Nikon W’s were tested at f/8 by Danny another forum member here and he found that the specifically the 180mm (and Schneider’s APO-Symmar 180mm) were sharp for 4x5 at that ”one stop down” aperture.

    The trouble is that the Copal 1 shutter limits my fastest shutter speed to 1/400 and in real life 1/3-1/2 stop slower than that.
    Dallas Texas HABS / HAER / HALS Photography
    Photographer/Author Marfa Flights: Aerial Views of Big Bend Country (Texas A&M University Press)
    Represented by Michael Duty Fine Art

  7. #47

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    Re: Aerials: 125-150mm sharp@ f/8 for 4x5 minimal vignetting

    Y'know, if you got a Speed Graphic you could have higher shutter speeds.

  8. #48

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    Re: Aerials: 125-150mm sharp@ f/8 for 4x5 minimal vignetting

    William Garnett...who took some really incredible aerials back in the day - often did so while piloting alone with his Graflex held over his shoulder. He'd worked out a routine which took advantage of his intimate feel for lighting, timing, placement, and...when he wasn't simply cutting the engine (which if I remember correctly he did not like doing)...those RPM ranges which presented the least amount of vibration. Amazing work!

  9. #49

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    Re: Aerials: 125-150mm sharp@ f/8 for 4x5 minimal vignetting

    ...cannot mention William Garnett without paying homage to Bradford Washburn!

  10. #50

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    Re: Aerials: 125-150mm sharp@ f/8 for 4x5 minimal vignetting

    Quote Originally Posted by pchaplo View Post
    Great site. I’m really enjoying his writings, images, and lens tests/comparisons. Thanks.
    Just let me add that, being always insteresting, lens performance can be secondary to obtain good results. How photographer manages DOF, aperture, focusing, alignment, shake, film usage, and post-processing may be more important than ultimate lens lp/mm in the field. For example a film may deliver no more than 50lp/mm in regular low contrast situation, and only with a very contrasty pattern it can resolve more, so other limiting factors may make high lens performance secondary.

    Also the sharp look of a photograph may be more related to other factors than to resolving power.

    I'm a big fan of measuring lp/mm, but I realize that it would be a secondary concept for a true artist. "Dovima with elephants" was made with a good lens, for sure, but this was a 1955 technology lens.

    For aerial photography you have to consider if your motion blur/shake is to limit resolving power in practice, making useless optical performance beyond certain level. And optical performance also depends on aperture, and from aperture and film you have a shutter speed that is related to blur/shake. But smaller aperture also is related to "on film" DOF, that will ensure focus if not perfect alignment and flatness.

    So, beyond lens performance you also have to make a good balance of the settings, and this may be more important than ultimate lp/mm measured in a lab.

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